Ground fitting



Aug 9 5 N. BUCHANAN ,1 2%? GROUNDING FITTING Filed NOV. 8, 1930 INVENTORSTEPHEN/Mm Patented Aug. 15, 1933 PATENT OFFICE GROUND FITTING StephenN. Buchanan, Elizabeth, N. 1., minor to The Thomas & Betta 00.,Elizabeth, N. J., a Corporation of New Jersey Application November 8,1930. Serial No. 494,283

2 Claims. (Cl. 173273) The invention relates to a grounding fitting bymeans of which a wire, such as a grounding wire, may be attached orclamped to the grounding fitting and the grounding fitting clamped to agrounded conductor, such as a water pipe, whereby a good electricalground is obtained for a conduit or other protective covering for awiring system. The wire clamp by means of which the grounding wire issecured to a grounding fitting or other structure also constitutes apart of the invention.

An object of the invention is to construct a grounding fitting which maybe wrapped and tightened around a grounded conductor for electricalcontact therewith and provides spaced wire clamping means between whicha grounding wire is positioned and clamped through the agency of awedging or pressure member which engages and bends at least one of thespaced clamping means to grip the grounding wire therebetween.

Another object of the invention is to produce a wire clamp in which oneor more wires are inserted between spaced wire clamping means or membersat least one of which is flexible, so that it can be bent to clamp thewires therebetween by means of pressure exerted through a wedging orpressure member.

Other objects of the invention will be more apparent from the followingdescription taken in connection with the accompanying drawing, in which:

Figure 1 is a cross-section through a grounded conductor or pipe havinga flexible band grounding fitting wrapped around the pipe and agrounding wire inserted between wire clamping means or portions of theband preparatory to clamping a grounding wire therebetween.

Figure 2 is an enlarged view of the wire clamping means of the groundingfitting with one of the spaced flexible clamping portions of theflexible band bent inwardly towa ds the other portion to clamp thegrounding wire therebetween.

Figure 3 is a cross-section through a conical washer or pressure memberwhich forms part of the operating means for the wire clamp.

Figure 4 is a view looking down upon the wire clamp with a groundingwire inserted therein, as viewed from line 44 of Figure 2.

The grounding fitting in its preferred form consists of a flexible bandwhich is wrapped around and tightened upon a grounded conductor such asa water pipe, to obtain good electrical connection therewith. Agrounding wire is then clamped to the grounding fitting so that anelectrical system may be grounded through the flexible band and groundedconductor.

The grounding fitting provides a flexible band 10 which is wrappedaround a grounded conductor, such as the water pipe P shown in Figure 1,in order to obtain electrical contact therewith. The flexible band 10has spaced wire clamping portions or members 11 and 12, forming part ofa wire clamping means, and between which a looped grounding wire W isplaced so that the wire is doubly gripped by the wire clamp. Obviouslytwo independent wires may be secured to the clamp instead'oi' the singlelooped wire W. The spaced wire clamping members 11 and 12 projectoutwardly or transversely of the flexible band 10 and from the pipe Pand a clamping screw 15 passes through passages in both members.

A bending abutment 13 is formed by bending the end of the flexible band10 at right angles to the wire clamping members 11 and 12 and parallelto the clamping screw 15 which is positioned then between the pipe P andthe abutment. The end of the abutmentv 13 engages the flat face of theother end 16 of the flexible band 10 so that the two ends of theflexible band may be drawn together by the clamping screw 15 to tightenthe band firmly upon the grounded conductor pipe P.

The operating means for the wire clamp and grounding fitting includesthe clamping screw 15 which passes through the spaced wire clampingportions or members 11 and 12 and through a hole 18 in the end 16 of theband 10. A number of spaced holes 18 are provided at spaced intervals inthe end 16 of the flexible band 10 so that the band may be secured topipe of various diameters and the clamping screw 15 passes through anyone of the holes 18 dependent upon the diameter of the pipe to which thegrounding fitting is secured. A pressure member which in its preferredconstruction is a conical washer 28 contacts with the wire clampingmember 11 and an operating nut 19 threaded upon the screw 15, completesthe operating means.

Tightening of the nut 19'upon the screw 15 draws the ends of theflexible band 10 towards each other and securely clamps the band uponthe pipe, as shown in Figure.2. The tightening of the nut 19 on thescrew 15 also bends the flexible wire clamping member 11 downwardly toclamp the grounding wire W between the members 11 and 12 and therebyobtaining good electrical contact between the flexible band 11 and thegrounding wire W. In order to clamp the wire W between the spaced wireclamping members 11 and 12, at least one of these members must beflexible or bendable although both membersmay have the samecharacteristic.

The spaced wire clamping members 11 and 12 between which the groundingwire W is positioned, are preferably constructed by raising a centralportion or band 11 from the center of the flexible band 10, as shown inFigure 4. Wire clamping members 12 then remain upon either side of thewire clamping member 11 and provide spaced wire clamping members ormeans between which the grounding wire W may be inserted and at leastone of the clamping members 11 or 12 is flexible so that the spacedclamping members may be drawn together to clamp or grip a grounding wiretherebetween.

By the construction above described, the separation of the spaced wireclamping portions or members 11 and 12 of the flexible band 10 formshoulders 22 and 23 at the ends of the wire clamping members. Now theconical head 25 of the clamping screw 15 not only bends one of the wireclamping portions, such as the member 11, to grip the grounding wire Wbetween the members 11 and 12, but also clamps the wire transverselyagainst the shoulders 22 and 23. Now the head of the ordinary conicalheaded screw, such as the head 25 of the screw 15, does not have adiameter sufiiciently large to contact with and bend the wire clampingmember 11 near enough to the wire W to firmly clamp the wire against theshoulders 22 and 23 particularly where the wire clamping members arerelatively long or the shoulders relatively widely separated.Incidentally, a long wire clamping member is more easily bent andassures more positive clamping of a ground wire in the wire clampingmeans than a shorter clamping member. A wedging or pressure member whichis a conical washer 28 in its preferred form, is therefore providedhaving an external conical surface 29 which contacts with the wireclamping member 11 adjacent to the wire W and bends this member so thatthe wire is firmly clamped against the shoulders 22 and 23 as well asbetween the members 11 and 12. This assures firm clamping of thegrounding wire W within the wire clamp. The conical wedging member 28may also have a conical central bore 30 to receive the conical head 25of the clamping screw 15.

The wire clamping members 11 and 12, at least one of which is a flexiblemember, and having the relatively widely spaced shoulders 22 and 23 atthe ends of the members provide a wire clamp irrespective of theirassociation with a grounding fitting of any type or of the flexible bandconstruction which is wrapped around a conductor as shown herein. Alsothe clamping screw 15 with the pressure member or conical washer 28forms the operating means whereby at least one of the flexible wireclamping mem bers 11 or 12 or both, may be bent or drawn together toclamp a wire W against the shoulders 22 and 23 and between the wireclamping members. The invention contemplates such a wire clamp,irrespective of whether it is associated with a grounding fitting, suchas that shown and described herein, or whether it is associated with anyother structure requiring the clamping of a wire thereto.

What is claimed is:

1. A grounding fitting comprising a flexible band to wrap around agrounded conductor, a center band struck from the flexible band adjacentone end thereof forming spaced flexible wire clamping members andextending transversely therefrom, spaced shoulders relatively widelyseparated formed by the wire clamping members, passages through bothmembers and through the flexible band, a clamping screw passing throughthe passages to clamp the band upon the conductor, and a pressure memberon the screw having a width substantially less than the inner spacingbetween the wires and contacting with one of the wire clamping membersto clamp the wire between the wire clamping members.

2. A grounding fitting comprising a flexible band to wrap around agroundedconductor, a center band struck from the flexible band adjacentone end thereof forming spaced flexible wire clamping members adjacentone end of the flexible band and extending transversely therefrom,spaced shoulders relatively widely separated formed by the wire clampingmembers, a bending abutment at the end of the flexible band and engagingthe other end thereof, passages through both members and through theflexible band, a clamping screw passing through the passages to clampthe band upon the conductor, a conical head on the clamping screw, and aconical washer on the screw having a diameter at its point of contactwith one of the wire clamping members substantially less than the innerspacing of the wires to bend the clamping member around the wire toclamp the wire between the members.

STEPHEN N. BUCHANAN.

